Method of for retarding dye fading during archival storage of developed color photographic film

Abstract

Dye fading during archival storage of developed color photographic film (17) is retarded by placing the film in a sealed, opaque vault (10), introducing a dry, pressurized inert gas into the vault while the latter is vented, and sealing the vault after the air within the vault has been purged and replaced by the inert gas. Preferably, the gas is nitrogen; and the vault is stored at a temperature below room temperature to preserve the color photographic emulsions on the film contained within the vault. For short-term storage, sodium thiocyanate pads (36) charged with water are placed within the vault. For long term storage, the interior of the vault is kept at a low relative humidity.

We claim: 
     
       1. A method for retarding dye fading during archival storage of developed color photographic film comprising the steps of: (a) placing the film in a sealed opaque vault;   (b) venting the vault;   (c) introducing a dry, pressurized inert gas into the vault while the latter is vented; and   (d) sealing the vault after the air in the vault is purged and replaced by the inert gas.   
     
     
       2. A method for retarding dye fading during archival storage of developed color photographic film according to claim 1 wherein the gas is nitrogen and the interior of the vault is maintained at a humidity of 40-50% by inclusion of water-charged pads of sodium thiocyanate therein. 
     
     
       3. A method for retarding dye fading during archival storage of developed color photographic film according to claim 1 wherein the gas is dry nitrogen. 
     
     
       4. A method for retarding dye fading during archival storage of developed color photographic film according to claim 3 including the step of storing the vault at a temperature below room temperature. 
     
     
       5. A method for retarding dye fading during archival storage of developed color photographic film according to claim 4 including the step of reopening the vault only after its contents have been returned to room temperature. 
     
     
       6. A method for retarding dye fading during archival storage of developed color photographic film according to claim 5 including the step of introducing moisture into the vault to return the relative humidity therein to the range 40-50% before using the film.